The Importance of Destructive Testing for Identifying Concealed Resultant Structural Damage

Vibration based structural health monitoring methods are usually dependent on the first several orders of modal information, such as natural frequencies, mode shapes and the related derived features. These information are usually in a low frequency range. These global vibration characteristics may not be sufficiently sensitive to minor structural damage. The alternative non-destructive testing method using piezoelectric transducers, called as electromechanical impedance (EMI) technique, has been developed for more than two decades. Numerous studies on the EMI based structural health monitoring have been carried out based on representing impedance signatures in frequency domain by statistical indicators, which can be used for damage detection. On the other hand, damage quantification and localization remain a great challenge for EMI based methods. Physics-based EMI methods have been developed for quantifying the structural damage, by using the impedance responses and an accurate numerical model. This article provides a comprehensive review of the exciting researches and sorts out these approaches into two categories: data-driven based and physics-based EMI techniques. The merits and limitations of these methods are discussed. In addition, practical issues and research gaps for EMI based structural health monitoring methods are summarized.

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Algorithm Development for the Non-Destructive Testing of Structural Damage

Applied Sciences ◽

10.3390/app9142810 ◽

2019 ◽

Vol 9 (14) ◽

pp. 2810 ◽

Cited By ~ 2

Author(s):

Azadeh Noori Hoshyar ◽

Maria Rashidi ◽

Ranjith Liyanapathirana ◽

Bijan Samali

Keyword(s):

Composite Materials ◽

Structural Damage ◽

Steel Plates ◽

Sensor Data ◽

Support Vector ◽

Non Destructive Testing ◽

Destructive Testing ◽

Validity Assessment ◽

Metal Plates ◽

Non Destructive

Monitoring of structures to identify types of damages that occur under loading is essential in practical applications of civil infrastructure. In this paper, we detect and visualize damage based on several non-destructive testing (NDT) methods. A machine learning (ML) approach based on the Support Vector Machine (SVM) method is developed to prevent misdirection of the event interpretation of what is happening in the material. The objective is to identify cracks in the early stages, to reduce the risk of failure in structures. Theoretical and experimental analyses are derived by computing the performance indicators on the smart aggregate (SA)-based sensor data for concrete and reinforced-concrete (RC) beams. Validity assessment of the proposed indices was addressed through a comparative analysis with traditional SVM. The developed ML algorithms are shown to recognize cracks with a higher accuracy than the traditional SVM. Additionally, we propose different algorithms for microwave- or millimeter-wave imaging of steel plates, composite materials, and metal plates, to identify and visualize cracks. The proposed algorithm for steel plates is based on the gradient magnitude in four directions of an image, and is followed by the edge detection technique. Three algorithms were proposed for each of composite materials and metal plates, and are based on 2D fast Fourier transform (FFT) and hybrid fuzzy c-mean techniques, respectively. The proposed algorithms were able to recognize and visualize the cracking incurred in the structure more efficiently than the traditional techniques. The reported results are expected to be beneficial for NDT-based applications, particularly in civil engineering.

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Structural Health Monitoring Experimental System Implemented in a Turboprop Commercial Aircraft

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.347.311 ◽

2007 ◽

Vol 347 ◽

pp. 311-317

Author(s):

Igor Bovio ◽

Leonardo Lecce

Keyword(s):

Structural Damage ◽

Damage Index ◽

Experimental System ◽

Experimental Tests ◽

Processing Technique ◽

Commercial Aircraft ◽

Destructive Testing ◽

Before And After ◽

Neural Network Algorithm ◽

Testing Field

The purpose of the paper is to present an innovative application within the Non Destructive Testing field based upon vibration measurements developed by the authors, and already tested for analysing damage of many structural elements. After having tested this application on different test articles in laboratory condition, experimental tests have been executed, in collaboration with the ATR company, on a turboprop ATR-72 aircraft, in order to validate the technique on a real aeronautical structure. The monitoring system have operated an off-line check on the structure, during the aircraft ground operations, as if it were a normal maintenance procedure. The results are reported in the paper. This proposed new method is based upon the acquisition and comparison of the Frequency Response Functions (FRFs) of the monitored structure before and after damage occurs. Structural damage modify the dynamic behaviour of a structure affecting its mass, stiffness and damping, and consequently the FRFs of a damaged structure, when compared with the FRFs of its sound configuration, making the identification, localization and quantification of damage possible. The activities presented in the paper focus mainly on a new FRFs processing technique based upon the determination of a representative “Damage Index” for identifying and analysing damage. Furthermore, a dedicated neural network algorithm has been elaborated to develop an automatic system which recognises positive samples, “healthy” states of the analysed structure, discarding negative ones, “damaged or perturbed” states of the analysed structure. From an architectural standpoint, piezoceramic patches have been used as both actuators and sensors.

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Non-Destructive Testing for Assessing Structural Damage and Interventions Effectiveness for Built Cultural Heritage Protection

Handbook of Research on Seismic Assessment and Rehabilitation of Historic Structures - Advances in Civil and Industrial Engineering ◽

10.4018/978-1-4666-8286-3.ch015 ◽

2015 ◽

pp. 448-499 ◽

Cited By ~ 7

Author(s):

Antonia I. Moropoulou ◽

Kyriakos C. Labropoulos

Keyword(s):

Cultural Heritage ◽

Structural Damage ◽

Moisture Transfer ◽

Destructive Testing ◽

Residual Properties ◽

Heritage Protection ◽

Ground Penetrating ◽

Non Destructive ◽

Correlate Data

Non-destructive techniques - NDT are used in the field of built cultural heritage protection, as they are applied in-situ and do not require destructive sampling. Infrared thermography is used for materials/decay mapping, assesses the compatibility and effectiveness of restoration materials and interventions, and reveals moisture transfer phenomena within structures. Ultrasonic testing assesses the residual properties of historic materials, reveals the decay layers and evaluates the effectiveness of consolidation treatments. Ground penetrating radar reveals the internal structure of masonries, identifies and locates subsurface voids, structural cracks and incontinuities. Portable imaging systems, in conjunction with digital image processing, are used for in-situ materials characterization, and for the study of the decay typologies. Data management systems correlate data from NDTs, from other methods and from seismic/environmental impact assessment analyses to evaluate the preservation state of a historic structure and to plan interventions.

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Non-Destructive Testing for Assessing Structural Damage and Interventions Effectiveness for Built Cultural Heritage Protection

Human-Computer Interaction ◽

10.4018/978-1-4666-8789-9.ch009 ◽

2015 ◽

pp. 178-229

Author(s):

Antonia I. Moropoulou ◽

Kyriakos C. Labropoulos

Keyword(s):

Cultural Heritage ◽

Structural Damage ◽

Moisture Transfer ◽

Destructive Testing ◽

Residual Properties ◽

Heritage Protection ◽

Ground Penetrating ◽

Non Destructive ◽

Correlate Data

Non-destructive techniques - NDT are used in the field of built cultural heritage protection, as they are applied in-situ and do not require destructive sampling. Infrared thermography is used for materials/decay mapping, assesses the compatibility and effectiveness of restoration materials and interventions, and reveals moisture transfer phenomena within structures. Ultrasonic testing assesses the residual properties of historic materials, reveals the decay layers and evaluates the effectiveness of consolidation treatments. Ground penetrating radar reveals the internal structure of masonries, identifies and locates subsurface voids, structural cracks and incontinuities. Portable imaging systems, in conjunction with digital image processing, are used for in-situ materials characterization, and for the study of the decay typologies. Data management systems correlate data from NDTs, from other methods and from seismic/environmental impact assessment analyses to evaluate the preservation state of a historic structure and to plan interventions.

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Structural Damage Identification by Detection Medium Technology

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.401-403.1493 ◽

2013 ◽

Vol 401-403 ◽

pp. 1493-1498

Author(s):

Zhen Fu Chen ◽

Zhong You Wang ◽

Jun Liu

Keyword(s):

Structural Damage ◽

Structural Integrity ◽

Infrared Imaging ◽

Damage Identification ◽

Wave Theory ◽

Pulse Method ◽

Ultrasonic Pulse ◽

Structural Testing ◽

Destructive Testing ◽

Detection Medium

There are two conventional techniques i.e. the approach based on structural testing and non-damaged detecting method, of which the former is partial to structural integrity analysis while the latter focuses on partial detection. The damage identification approach is discussed from the perspective of detection medium in the paper. And non-destructive testing in civil engineering (NDT-CE), of which the research status and existing issues are presented, can be attributed into three categories as following: one is based on the stress wave theory, such as impact-echo method, acoustic emission technique and ultrasonic pulse method; one employs the mechanism of electromagnetic wave propagation on behalf of GPR; one uses radiography as the medium, for instance, infrared imaging and computerized tomography. It is emphasized that ground penetrating radar (GPR) has been applied in practice and studied more and more, and moreover, the prospects in the field are provided.

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Enhancement of shearography-based damage identification using best tree wavelet packet analysis

MATEC Web of Conferences ◽

10.1051/matecconf/201820406002 ◽

2018 ◽

Vol 204 ◽

pp. 06002

Author(s):

Andrzej Katunin ◽

Hernani Lopes ◽

José Viriato Araújo dos Santos

Keyword(s):

Wavelet Transforms ◽

Structural Damage ◽

Damage Identification ◽

Experimental Testing ◽

Wavelet Packet ◽

High Sensitivity ◽

Industrial Applications ◽

Wavelet Packet Analysis ◽

Destructive Testing ◽

Signal Processing Methods

Shearography found many industrial applications as a non-destructive testing method due to its high spatial resolution and contactless measurements. However, to detect small structural damage, shearography should be enhanced by applying advanced signal processing methods to results of experimental testing. In this paper, the authors present an enhanced method based on the best tree wavelet packet analysis, which allows for extraction of the most informative nodes from the 2D wavelet packet decomposition tree. The proposed method is more effective than typical wavelet transforms due to its ability of adaptive selection of the best basis. The efficiency of the method was verified experimentally on damaged plates. The obtained results clearly show high sensitivity to the introduced small damage, which make the method attractive for industrial applications.

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Damage Diagnosis of Radial Gate Based on Modal Strain Energy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.71-78.4240 ◽

2011 ◽

Vol 71-78 ◽

pp. 4240-4243

Author(s):

Jian Wei Zhang ◽

Yi Na Zhang ◽

Sheng Zhao Cheng

Keyword(s):

Structural Damage ◽

Strain Energy ◽

Theoretical Research ◽

Destructive Testing ◽

Modal Strain Energy ◽

Damage Diagnosis ◽

Engineering Research ◽

Research Problems ◽

Good Identification ◽

Radial Gate

Non-destructive testing and safety monitoring of structure has been a hot and difficult engineering research problems, and an effective extraction of damage characteristic factor is a critical and theoretical research on structural damage detection and monitoring technology. The basic theory of modal strain energy and the steps to damage diagnosis are discussed in the paper.A a radial gate with different damaged locations and damaged degree is studied,and the results show that modal strain energy can be used as structural damage location sensitive factor,and that the indicator can be a very good identification of the location and extent of structural damage,and that the results of damage diagnosis are clear and reliable.

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Monitoring the Dynamic Behaviour of Concrete Bridges Using Non-Contact Sensors (IBIS-S)

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.846.225 ◽

2016 ◽

Vol 846 ◽

pp. 225-230 ◽

Cited By ~ 4

Author(s):

Li Hai Zhang ◽

Maizuar Maizuar ◽

Priyan Mendis ◽

Colin Duffield ◽

Russell Thompson

Keyword(s):

Structural Damage ◽

Traffic Accidents ◽

Rapid Assessment ◽

Computational Modelling ◽

Transportation Systems ◽

Concrete Bridges ◽

Destructive Testing ◽

Public And Private ◽

Deterioration Rate ◽

Truck Loading

The maintenance and operation of bridges represent a significant investment in both the public and private domains. In practice, the structural damage of a bridge that accumulates over its life-span is a result of continuous degradation caused mainly by traffic conditions and sudden extreme events (e.g. flooding, fires and severe traffic accidents). However, under heavy truck loading, the deterioration rate of a bridge can be accelerated. As the use of heavier articulated trucks becomes increasingly popular in contemporary freight transportation systems, the development of modern Non-Destructive Testing (NDT) techniques in conjunction with computational modelling becomes necessary. The advancement in this area will allow rapid assessment of the structural health of bridges and detection of ongoing damage to enhance the structural performance of bridges.

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Evaluation of single-electron movies of glutamine synthetase molecules

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075191 ◽

1983 ◽

Vol 41 ◽

pp. 280-281

Author(s):

W. Kunath ◽

E. Zeitler ◽

M. Kessel

Keyword(s):

Electron Microscope ◽

Glutamine Synthetase ◽

Electron Irradiation ◽

Structural Damage ◽

Structural Changes ◽

Single Electron ◽

Continuous Series ◽

Digital Recording ◽

Recording Device ◽

Low Exposure

The features of digital recording of a continuous series (movie) of singleelectron TV frames are reported. The technique is used to investigate structural changes in negatively stained glutamine synthetase molecules (GS) during electron irradiation and, as an ultimate goal, to look for the molecules' “undamaged” structure, say, after a 1 e/Å2 dose.The TV frame of fig. la shows an image of 5 glutamine synthetase molecules exposed to 1/150 e/Å2. Every single electron is recorded as a unit signal in a 256 ×256 field. The extremely low exposure of a single TV frame as dictated by the single-electron recording device including the electron microscope requires accumulation of 150 TV frames into one frame (fig. lb) thus achieving a reasonable compromise between the conflicting aspects of exposure time per frame of 3 sec. vs. object drift of less than 1 Å, and exposure per frame of 1 e/Å2 vs. rate of structural damage.

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